A cover device includes a cover plate having at least one recessed section defining an internal volume. A separating element is inserted in the recessed section and delimits the internal volume. The separating element is configured to permit the internal volume to fluidly communicate through the separating element. At least an edge portion of the cover plate is provided with a sealing element for abutment on an opposing surface of a structure to be sealed by the cover device. The sealing element is disposed at least along an edge of the recessed section and fixedly connects the cover plate with the separating element in a sealed manner.